1949 Mercury Rear End Question

I have a 1949 mercury rear end with what is was told was a set of 3.73 gears....from the way she is screaming i would think 4.11's. My 400 ****** puts a lot of strain on my sbc...in hindsight i should have found a 700 ****** but it is 2 late now. She is working way 2 hard at 60 mph.
I need to find a set of gears to make it highway friendly.
I have not had any luck finding a shorter gear.
Can anyone point me in the right direction for a new set of gears or does anyone know of gear swap from a ford or lincoln or another year of mercury that might cure my problem?
i looked into putting in a ford 9 in but the cost was lot more then i wanted to spend. After a new rear end, cutting down the tubes and axles, new shoes and drums and the whole bit i would be better just finding new gears.
Thanks in advance for you help.

John

 

My '49 Lincoln coupe has a 4.27:1 rear...
So not any better for you.

.

 

get your measuring tape out and see what you have drum to drum, then take your tape measure to the wrecking yard and tell them what you need for width and gear size. Might be the only cutting done is when they use the hot wrench to get it out.

 

It is my understanding that a early 60's Ford F-100 rear end is the correct width. The F-100 would also still have the same wheel pattern as your stock rims ( no more expense $$$ ) ... The rear end is a 9 inch Ford series rear, so most any gear ratio can be installed, it would have the larger axle bearings ( for a heavy Mercury ) and decent, parts available brakes and brake parts.

 

Im running an 8.8 disc brake 3:73 trac-lock out of a ford explorer. Its 59.5 inches and you can use 1/2 spacers to get it to 60.5 if you want.

 

Thanks for you help. I have been trying to hunt down gears all night and day. I will begin to take a look for something that measures the same width. I just cant believe that ford, mercury and lincoln didnt share any parts. That the rear ends were so different they couldnt swapped..i guess they didnt have to worry about being cost effective in late 40's.

John

 

49-51 Mercs with automatic trans came with 3:31 gears. If you can find one( ebay?) it will bolt right in. The 71-73 Ford Mustang rear is exactly the same width 61 1/4" (wheel mounting surface to wheel mounting surface) as the stock Merc. But the bolt pattern is 4 1/2"- not the same as Merc. You would have to get new wheels.

 

Yep, the auto is 3.31 gearing, but its 51 only (first year) so as you can imagine its hard to come by em. Was your 49 originally an overdrive car? If so you might just have 4.27s out back, which blow ***. The non OD I think is 3.73 or close (might be higher) and I had a 51 with them in it, that was terrible. My 50 was an overdrive car so I put a 3.73 rear in (F100) just cuz I wanted to keep the stock pattern but it wasnt great with my 302/C4. My 51 now has a 9" with 2.7x gears and it should be nice, and my next 51 will be on an Olds ch***is (79 98) or at least use the drivetrain, which is again around 2.7x gears. Yeah I might lose some uumph off the line but whatever, highway cruising will be great.

The width outside (wheel mounting surface) is 61", just grab something from the boneyard. Also check out Carnut.com, there is a rear width chart that has a few matches for the Merc. Good luck!

 

Thanks for the info. This confirms what i was told that a set of 51 OD gears are what i am searching for. i have a non OD car with 3.73 gears.

John

 

Mine has a 9" with,newly installed,3.16 gears! It had 4.somethings before! About 4k,rpm's, on the frwy... It turns 2100 now!!! You can also use a Maverick,or Granada rearend. Do yourself a favor and take the center section out and count the teeth BEFORE you install it in the car. Don't take anybodies word for what gears are in it.

 

I'm using a Granada rear in my 49. It is too narrow, useing 1/2 inch spacers and could easy use an inch more. Time for some custom wheels!!.........OLDBEET

 

Mine's actually too wide,LOL!!! I need to get some wheels that have 1" more backspaceing.

 

I got a 70 ranchero in my 50....its real tight gettin a tire on and off.....Lowlidx50

 

i usually put a 9" out of a 72 and lower 1/2 ford truck

 

My '51 rolls on a later frame, supposedly Pontiac, but I have to get a few folks to look at it with me since I really don't know.

 

try a rear from a 52-56 mercury,wagon or reg,also ford. these came with higher gears

 

the rear i used is from a 82-93 chev 4x4 blazer. dont remember the width, but i know that it's fine with wheels and caddy caps. these should be available in a 3:42 or 3:73 ratio and there plentiful (at least round here)

 

Your rear end is a ****er type.It's either a 41 or 44 series. Check with your local 4 wheel drive shop , as they used those rear ends for years in many different makes of cars & pickups, ie. 4x4's also.They should be able to find a good ratio for yours.

 

OD gears are going to be worse. If you have 3.73, you wouldnt want to go to a 4.27...that would be worse.

 

Taller tires.

 

That's what I like to hear....

 

Non Od cars had 3:92 gears. I'm gonna run a flathead with the 3spd Od and the non Od rearend.

 

I have a 51 merc OD rear end for sale if you change your mind. Came out of my Merc.
4:27 ratio.

 

That would be a '51 only. No automatics in '49-'50.

 

old thread but my 50 will have 68 f-100 rear with 3:25 ratio!